The following relates generally to wireless communications, and more specifically to cross-correlation reduction for control signals.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may be referred to as New Radio (NR) systems. These systems may employ technologies such as code-division multiple access (CDMA), time-division multiple access (TDMA), frequency-division multiple access (FDMA), orthogonal frequency-division multiple access (OFDMA), and discrete Fourier transform-spread-orthogonal frequency-division multiplexing (DFT-s-OFDM). A wireless multiple-access communications system may include a number of base stations or network access nodes, each simultaneously supporting communication for multiple communications devices, which may be otherwise known as user equipment (UE).
Some wireless systems (e.g., LTE, NR) may support control signaling (e.g., physical downlink control channel (PDCCH) signaling) in which a UE performs a large number (e.g., forty or more) of blind decodes for PDCCH in a given slot. Each blind decode may, for instance, correspond to a particular combination of parameter hypotheses (e.g., a search space, tone offset, codeword size, etc.). In some cases, a blind decode hypothesis may land on a set of resources that actually carry a valid control signal that is intended for another user or another group of users. That is, the blind decode hypothesis may have the correct combination of parameter hypotheses (e.g., search space, tone offset, etc.) except the control signal may use a radio network temporary identifier (RNTI) of a different UE. Such codewords may undergo most of all of a decoding process before being classified as intended for another device, and the decoding process may consume power. Improved techniques for cross-correlation reduction for control signals may be desired.